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Herein, we report a computational algorithm that follows a spectroscopist-driven elucidation process of the structure of an organic molecule based on IR, $^1$H and $^{13}$C NMR, and MS tabular data. The algorithm is independent from database searching and is based on a bottom-up approach, building the molecular structure from small structural fragments visible in spectra. It employs an analytical combinatorial approach with a graph search technique to determine the connectivity of structural fragments that is based on the analysis of the NMR spectra, to connect the identified structural fragments into a molecular structure. After the process is completed, the interface lists the compound candidates, which are visualized by the WolframAlpha computational knowledge engine within the interface. The candidates are ranked according to the predefined rules for analyzing the spectral data. The developed elucidator has a user-friendly web interface and is publicly available (http://schmarnica. si).

Cilj je omogućiti predviđanje konformacije triptaminskih tijela u kristalnim fazama produkata njihovih reakcija s karboksilnim kiselinama i odrediti njihovu iskoristivost kao potencijalnih molekula za dizajniranje kristalnih struktura. Dodatno, prepoznati čimbenike koji određuju torzijske kutove C13–C12–C11–N11 i C110–C13–C12–C11. Ciljani produkti pripremljeni su miješanjem metanolnih i metanol-benzenskih otopina triptamina i halogeniranih karboksilnih kiselina (2-klor-5-nitrobenzojeve, 2-klorbenzojeve, 3-klorbenzojeve, 2-brombenzojeve, 4-brombenzojeve, 3-jodbenzojeve, trikloroctene i mezo-dibromjantarne kiseline). Dobiveni produkti karaterizirani su ATR i 15N NMR spektroskopijom. Kemijski pomak atoma dušika uspoređivan je u odnosu na dva referentna 15N NMR spektra – spektar čistog triptamina i spektar triptaminijevog hidroklorida (za kojeg je pretpostavljeno da je potpuno ionski kristal). Prema dobivenim ATR IR i 15N NMR spektrima, dobivene produkte nije moguće jednoznačno karakterizirati kao kokristalne produkte ili ionske soli. U metodičkom dijelu dana je usporedba starog i novog osnovnoškolskog programa kemije te je predložen 90-minutni nastavni sat koji se temelji na strategiji učenja otkrivanjem, a u kojem učenici uče o povezanosti građe sustava na atomsko-molekulskoj razini s makroskopskim svojstvima tvari. The goal was to grow data that will enable prediction of conformation of tryptaminic moieties in crystal phases of their aducts with carboxylic acids and determine their potential to be used as tectons in crystal structure design. Additionally, to recognize parameters that influence or determine torsion angles C13–C12–C11–N11 i C110–C13–C12–C11. Aducts were prepared by mixing methanol or benzene-methanol solutions of tryptamine and halogenated acids (2- chloro-5-nitrobenzoic acid, 2-chlorbenzoic acid, 3-chlorobenzoic acid, 2-bromobenzoic acid, 3-bromobenzoic acid, 4-bromobenzoic acid, 3-iodobenzoic acid, 4-iodobenzoic acid, trichloroacetic acid and mezo-dibromosuccinic acid). Products were characterized by ATR IR and 15N NMR spectroscopy. Chemical shift of nitrogen atoms were compared with two references: the chemical shifts of analogous nitrogen atoms in solid pure tryptamine and in solid of tryptaminium hydrochloride. According to measured ATR IR and 15N NMR spectra it is not possible to uneqvivocally classify products as cocrystals or salts. In methodical part a comparison of old and new primary school chemical syllabuses was given together with a 90-minute classroom founded on inquiry learning strategy during which pupils will learn how macroscopic properties of a compound are related to its structure on atomicmolecular level.

Istražene su reakcije građevnog bloka A3[ML3]·3H2O {A = K+, NH4+ ili [(C4H9)4N)4]+; M = Cr3+ ili Fe3+; L = C2O42– ili C6O4Cl22–}, bakrove(II) soli i N-donorskog liganda (imidazola, 2,2'-bipiridina, 1,10-fenantrolina ili 2,2':6',2''-terpiridina), uz dodatak tetraklorkinona i KI u nekim reakcijama, tehnikom nadslojavanja ili u hidrotermalnim uvjetima. Priređen je 51 novi spoj: 35 oksalatnih, od čega je 29 heterometalnih (19 [CuIICrIII] i 10 [CuIIFeII/III]), i 12 kloranilatnih, od čega je 7 heterometalnih (4 [CuIICrIII] i 3 [CuIIFeIII]). Pripravljeno je 9 kompleksa s mononuklearnim, 11 s dinuklearnim, 5 s trinuklearnim, 2 s tetranuklearnim i 1 s heksanuklearnim jedinkama. Priređeno je i 13 jednodimenzijskih te 6 trodimenzijskih koordinacijskih polimera. Svi su spojevi okarakterizirani IR spektroskopijom, te su im određene molekulske i kristalne strukture. Za 15 spojeva su njihova svojstva ispitana metodama termičke analize te magnetska svojstva za 14 spojeva koji sadrže premošćujuću oksalatnu skupinu, odnosno električna svojstva za 7 spojeva. 5 heterometalnih oksalatnih kompleksa je proučavano u obliku molekulskih prekursora za dobivanje mješovitih metalnih oksida termičkom razgradnjom; dobivenom jednofaznom sustavu CuCrO2 istražena je fotokatalitička aktivnost u reakciji cijepanja vode. Kod 2 spoja je uočen fotokromizam, odnosno termokromizam kod 1. The reactions of building block A3[ML3]·3H2O {A = K+, NH4+ or [(C4H9)4N)4]+; M = Cr3+ or Fe3+; L = C2O42– or C6O4Cl22–}, copper(II) salt and N-donor ligand (imidazole, 2,2'-bipyridine, 1,10-phenanthroline or 2,2':6',2"-terpyridine), with the addition of tetrachloroquinone and KI in some reactions were studied, in layering technique or in hydrothermal conditions. 51 new compounds were prepared: 35 oxalate-based {29 heterometallic [19 (CuIICrIII) and 10 (CuIIFeII/III)]}, and 12 chloranilate {7 heterometallic [4 (CuIICrIII) and 3 [CuIIFeIII]} were isolated. In these reactions 9 complexes with mononuclear, 11 with dinuclear, 5 with trinuclear, 2 with tetranuclear and 1 with hexanuclear units were obtained. 13 one-dimensional and 6 three-dimensional coordination polymers were formed. IR and structural characterization was done for all the complexes. For 15 compounds thermal properties were investigated, for 14 compounds with bridging oxalate group magnetic properties, and for 7 compounds electric properties were studied. 5 selected heterometallic oxalate complexes were tested as molecular precursors for mixed-metal oxides and single-phased CuCrO2 was obtained. Its photocatalytic activity in water splitting reaction was tested. 2 compounds showed photochromism and 1 thermochromism.

Snimljen je infracrveni spektar asparaginske kiseline.Dobivene vrpce su identificirane usporedbom s prije objavljenim radovima iz infracrvene spektroskopije aminokiselina i izračunatim frekvencijama vibracija unutar programa Gaussian i GaussView. Potvrđene su zwitterionska struktura i unutarmolekulske vodikove veze. Svrha zadatka: Analizirati spektar asparaginske kiseline na osnovi njene molekulske strukture te asocirati vibracije sa vrpcama u dobivenom spektru. The infrared spectrum of aspartic acid was recorded and measured. The obtained ribbons were identified by comparison with previously published papers from the infrared spectroscopy of amino acids and calculated vibration frequencies within the Gaussian and GaussView programs. The zwitterionic structure and the intramolecular hydrogen bonds were confirmed. Goal: The analysis of the asparagine acid spectrum on the basis of its molecular structure and associate the vibration with the bands in the obtained spectrum.

Apsorpcija gustih para cezijevih dimera precizno je izmjerena u bliskom infracrvenom području (700 - 1300 nm), pri temperaturama od 600 do 700 K. U tom području valnih duljina uočavaju se cezijev prvi rezonantni dublet s tripletnim satelitima u krilima linija te molekulske A-X i B-X vrpce. Ove spektralne pojave nastaju optičkim prijelazima iz osnovnog singletnog i tripletnog elektronskog stanja, u pobuđena elektronska stanja čije energije teže u 6S + 6P asimptotu. Koristeći recentne ab initio račune adijabatskih elektronskih energija molekulskih stanja i odgovarajućih dipolnih momenata prijelaza, napravljene su poluklasične i kvantnomehaničke simulacije spektara za temperature identične eksperimentalnim temperaturama. Na taj način testirana je točnost teorijskih molekulskih potencijalnih krivulja, dipolnih momenta, kao i samih modela simulacije spektara.

Reaktivnost trimetilsililnih derivata ciklopropena.